Seats for individuals to sit in come in a wide variety of shapes and materials. Typically, a seat will have a seat bottom and a seat back, the seat bottom being the component upon which a person will sit and the seat back providing support for the person's back.
Motor vehicles such as automobiles, trucks, tractors and the like typically have seats with seat bottoms and seat backs with some of the seats operable for the seat back to tilt in a forward and rearward direction. In addition, some seats for motor vehicles are known as 60/40 seats, such a seat typically made from two major sections. One of the sections includes a seating structure for an individual to sit on, along with an adjoining side section that can be used to attach an armrest, or in the alternative, store the armrest in an upright position and provide a seating region for an additional passenger. Such a seating portion is known as the 60 part of the 60/40 seat. The 40 part is simply a single passenger seat.
With the increase of fuel costs and the corresponding desire for increased fuel efficiency, motor vehicles are developed with reduced weight as a goal. However, all of the components of the vehicles, including seat structures, are required to meet Federal Safety Standards. One method of making a seat that is both lightweight and meets appropriate safety standards is to use a polymer as a material of construction fabrication. For example, heretofore seat structures have been made from blow molding of a polymer in order to produce a low cost plastic molding structure having relatively light weight when compared to other materials such as steel, aluminum and the like. For example, U.S. Pat. No. 4,390,209 discloses a plastic seat back frame work and a method of manufacture. Likewise, U.S. Pat. No. 5,253,924 discloses a blow molded seat back with a reinforcing member.
Although lightweight and sufficiently strong seat structures have been provided using blow molding, this method has its limitations. For example, a blow molded component must have a generally uniform thickness throughout the part, the control of the thickness can be less than desirable and the complexity of the component can be limited. As such, seat back supports have been limited to relatively simple shapes that have excess material, excess weight and limited integral attachment features. In addition, blow molded seat back supports have required that steel plates be attached thereto in order for a component such as an armrest and/or an adjustable headrest support structure to be attached thereto.
In light of these limitations, a seat back support having sufficient strength and toughness to meet Federal Safety Standards, and yet be lightweight and incorporate integral attachment structures would be desirable. In addition, a process for making such a seat back structure would also be desirable.